struct group *fgetgrent(FILE *f)
{
static char *line, **mem;
static struct group gr;
size_t size=0, nmem=0;
return __getgrent_a(f, &gr, &line, &size, &mem, &nmem);
}
struct group *getgrent()
{
static char *line, **mem;
static struct group gr;
size_t size=0, nmem=0;
if (!f) f = fopen("/etc/group", "rb");
if (!f) return 0;
return __getgrent_a(f, &gr, &line, &size, &mem, &nmem);
}
static int getgr_r(const char *name, gid_t gid, struct group *gr, char *buf, size_t size, struct group **res)
{
FILE *f;
char *line = 0;
size_t len = 0;
char **mem = 0;
size_t nmem = 0;
int rv = 0;
size_t i;
int cs;
pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
f = fopen("/etc/group", "rbe");
if (!f) {
rv = errno;
goto done;
}
*res = 0;
while (__getgrent_a(f, gr, &line, &len, &mem, &nmem)) {
if (name && !strcmp(name, gr->gr_name)
|| !name && gr->gr_gid == gid) {
if (size < len + (nmem+1)*sizeof(char *) + 32) {
rv = ERANGE;
break;
}
*res = gr;
buf += (16-(uintptr_t)buf)%16;
gr->gr_mem = (void *)buf;
buf += (nmem+1)*sizeof(char *);
memcpy(buf, line, len);
FIX(name);
FIX(passwd);
for (i=0; mem[i]; i++)
gr->gr_mem[i] = mem[i]-line+buf;
gr->gr_mem[i] = 0;
break;
}
}
free(mem);
free(line);
fclose(f);
done:
pthread_setcancelstate(cs, 0);
return rv;
}
int __getgr_a(const char* name, gid_t gid, struct group* gr, char** buf, size_t* size, char*** mem,
size_t* nmem, struct group** res) {
FILE* f;
int rv = 0;
*res = 0;
f = fopen("/etc/group", "rbe");
if (!f) {
rv = errno;
goto done;
}
while (!(rv = __getgrent_a(f, gr, buf, size, mem, nmem, res)) && *res) {
if ((name && !strcmp(name, (*res)->gr_name)) || (!name && (*res)->gr_gid == gid)) {
break;
}
}
fclose(f);
if (!*res && (rv == 0 || rv == ENOENT || rv == ENOTDIR)) {
int32_t req = name ? GETGRBYNAME : GETGRBYGID;
int32_t i;
const char* key;
int32_t groupbuf[GR_LEN] = {};
size_t len = 0;
size_t grlist_len = 0;
char gidbuf[11] = {};
int swap = 0;
char* ptr;
if (name) {
key = name;
} else {
if (gid > UINT32_MAX) {
rv = 0;
goto done;
}
key = itoa(gidbuf, gid);
}
f = __nscd_query(req, key, groupbuf, sizeof groupbuf, &swap);
if (!f) {
rv = errno;
goto done;
}
if (!groupbuf[GRFOUND]) {
rv = 0;
goto cleanup_f;
}
if (!groupbuf[GRNAMELEN] || !groupbuf[GRPASSWDLEN]) {
rv = EIO;
goto cleanup_f;
}
if (groupbuf[GRNAMELEN] > SIZE_MAX - groupbuf[GRPASSWDLEN]) {
rv = ENOMEM;
goto cleanup_f;
}
len = groupbuf[GRNAMELEN] + groupbuf[GRPASSWDLEN];
for (i = 0; i < groupbuf[GRMEMCNT]; i++) {
uint32_t name_len;
if (fread(&name_len, sizeof name_len, 1, f) < 1) {
rv = ferror(f) ? errno : EIO;
goto cleanup_f;
}
if (swap) {
name_len = bswap_32(name_len);
}
if (name_len > SIZE_MAX - grlist_len || name_len > SIZE_MAX - len) {
rv = ENOMEM;
goto cleanup_f;
}
len += name_len;
grlist_len += name_len;
}
if (len > *size || !*buf) {
char* tmp = realloc(*buf, len);
if (!tmp) {
rv = errno;
goto cleanup_f;
}
*buf = tmp;
*size = len;
}
if (!fread(*buf, len, 1, f)) {
rv = ferror(f) ? errno : EIO;
goto cleanup_f;
}
if (groupbuf[GRMEMCNT] + 1 > *nmem) {
if (groupbuf[GRMEMCNT] + 1 > SIZE_MAX / sizeof(char*)) {
rv = ENOMEM;
goto cleanup_f;
}
char** tmp = realloc(*mem, (groupbuf[GRMEMCNT] + 1) * sizeof(char*));
if (!tmp) {
rv = errno;
goto cleanup_f;
}
*mem = tmp;
*nmem = groupbuf[GRMEMCNT] + 1;
}
if (groupbuf[GRMEMCNT]) {
mem[0][0] = *buf + groupbuf[GRNAMELEN] + groupbuf[GRPASSWDLEN];
for (ptr = mem[0][0], i = 0; ptr != mem[0][0] + grlist_len; ptr++)
if (!*ptr)
mem[0][++i] = ptr + 1;
mem[0][i] = 0;
if (i != groupbuf[GRMEMCNT]) {
rv = EIO;
goto cleanup_f;
}
} else {
mem[0][0] = 0;
}
gr->gr_name = *buf;
gr->gr_passwd = gr->gr_name + groupbuf[GRNAMELEN];
gr->gr_gid = groupbuf[GRGID];
gr->gr_mem = *mem;
if (gr->gr_passwd[-1] || gr->gr_passwd[groupbuf[GRPASSWDLEN] - 1]) {
rv = EIO;
goto cleanup_f;
}
if ((name && strcmp(name, gr->gr_name)) || (!name && gid != gr->gr_gid)) {
rv = EIO;
goto cleanup_f;
}
*res = gr;
cleanup_f:
fclose(f);
goto done;
}
done:
if (rv)
errno = rv;
return rv;
}
